/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.catalina.core;

import org.apache.catalina.Wrapper;
import org.apache.catalina.comet.CometEvent;
import org.apache.catalina.connector.Request;
import org.apache.catalina.connector.Response;
import org.apache.catalina.valves.ValveBase;
import org.apache.tomcat.util.buf.MessageBytes;

import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * Valve that implements the default basic behavior for the
 * <code>StandardContext</code> container implementation.
 * <p>
 * <b>USAGE CONSTRAINT</b>:  This implementation is likely to be useful only
 * when processing HTTP requests.
 *
 * @author Craig R. McClanahan
 */
final class StandardContextValve extends ValveBase {

	/**
	 * The descriptive information related to this implementation.
	 */
	private static final String info =
			"org.apache.catalina.core.StandardContextValve/1.0";

	public StandardContextValve() {
		super(true);
	}

	/**
	 * Return descriptive information about this Valve implementation.
	 */
	@Override
	public String getInfo() {
		return (info);
	}

	/**
	 * Select the appropriate child Wrapper to process this request,
	 * based on the specified request URI.  If no matching Wrapper can
	 * be found, return an appropriate HTTP error.
	 *
	 * @param request  Request to be processed
	 * @param response Response to be produced
	 * @throws IOException      if an input/output error occurred
	 * @throws ServletException if a servlet error occurred
	 */
	@Override
	public final void invoke(Request request, Response response)
			throws IOException, ServletException {

		// Disallow any direct access to resources under WEB-INF or META-INF
		MessageBytes requestPathMB = request.getRequestPathMB();
		if ((requestPathMB.startsWithIgnoreCase("/META-INF/", 0))
				|| (requestPathMB.equalsIgnoreCase("/META-INF"))
				|| (requestPathMB.startsWithIgnoreCase("/WEB-INF/", 0))
				|| (requestPathMB.equalsIgnoreCase("/WEB-INF"))) {
			response.sendError(HttpServletResponse.SC_NOT_FOUND);
			return;
		}

		// Select the Wrapper to be used for this Request
		Wrapper wrapper = request.getWrapper();
		if (wrapper == null || wrapper.isUnavailable()) {
			response.sendError(HttpServletResponse.SC_NOT_FOUND);
			return;
		}

		// Acknowledge the request
		try {
			response.sendAcknowledgement();
		} catch (IOException ioe) {
			container.getLogger().error(sm.getString(
					"standardContextValve.acknowledgeException"), ioe);
			request.setAttribute(RequestDispatcher.ERROR_EXCEPTION, ioe);
			response.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
			return;
		}

		if (request.isAsyncSupported()) {
			request.setAsyncSupported(wrapper.getPipeline().isAsyncSupported());
		}
		wrapper.getPipeline().getFirst().invoke(request, response);
	}

	/**
	 * Select the appropriate child Wrapper to process this request,
	 * based on the specified request URI.  If no matching Wrapper can
	 * be found, return an appropriate HTTP error.
	 *
	 * @param request  Request to be processed
	 * @param response Response to be produced
	 * @param event
	 * @throws IOException      if an input/output error occurred
	 * @throws ServletException if a servlet error occurred
	 */
	@Override
	public final void event(Request request, Response response, CometEvent event)
			throws IOException, ServletException {

		// Select the Wrapper to be used for this Request
		Wrapper wrapper = request.getWrapper();

		wrapper.getPipeline().getFirst().event(request, response, event);
	}
}
